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TROJ64_INSTOL.USR
Malware type: Trojan
Destructive: No
Platform: Windows XP (64-bit), Windows Vista (64-bit), Windows 7 (64-bit)
Encrypted: No
In the wild: Yes

Overview


Infection Channel: Downloaded from the Internet, Dropped by other malware

This malware injects certain processes with its malicious component, forcing the download and execution of malware on the affected system.

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Technical Details


File size: 73,728 bytes
File type: EXE
Memory resident: Yes
Initial samples received date: 06 Feb 2013

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan s DLL component is injected to the following process(es):

  • lsass.exe

Other Details

This Trojan requires the following additional components to properly run:

  • {Malware Path and File Name}.dll - detected as TROJ64_INJECT.USR

NOTES:

This malware injects the normal process lsass.exe with its malicious DLL component detected as TROJ64_INJECT.USR.

It loads its DLL component using the following parameters:

    {Malware Path and File Name}.exe -s TRUE {string 1} {string 2}

where {string 1} and {string 2} are as follows:

  • string 1 = encrypted Malware Path and File Name of TROJ64_INJECT.USR
  • string 2 = encrypted URL

It registers itself as a service to enable automatic execution on startup:

  • {Malware File Name}

Solution


Minimum scan engine: 9.300
First VSAPI Pattern File: 9.708.08
First VSAPI Pattern Release Date: 06 Feb 2013
VSAPI OPR Pattern Version: 9.709.00
VSAPI OPR Pattern Release Date: 06 Feb 2013

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Scan your computer with your Trend Micro product and note files detected as TROJ64_INSTOL.USR

Step 3

Restart in Safe Mode

[ Learn more ]

Step 4

Disable this malware service

[ Learn more ]
  • {Malware File Name}

Step 5

Search and delete the file detected as TROJ64_INSTOL.USR

[ Learn more ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files in the search result.

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ64_INSTOL.USR. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

NOTES:
Before performing the last step of the Solution procedure, first identify and delete the malware component detected as TROJ64_INJECT.USR.


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Analysis By: Rhena Inocencio

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